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 ###Instrução: Qual é a renda per capita para uma renda familiar mediana de $50,755?
 ###Tabelas: CREATE TABLE core_county_population_statistics (core_county_population_statistics_id AUTO_INCREMENT PRIMARY KEY, County VARCHAR, 1900 INT, 1930 INT, 1950 INT, 2000 INT, 2006 est. INT) CREATE TABLE 4-8-4 (4-8-4_id AUTO_INCREMENT PRIMARY KEY, Class VARCHAR, Wheel arrangement VARCHAR, Fleet number(s) VARCHAR, Manufacturer VARCHAR, Serial numbers VARCHAR, Year made VARCHAR, Quantity made VARCHAR, Quantity preserved VARCHAR, Year(s) retired VARCHAR) CREATE TABLE past_champions_in_the_field (past_champions_in_the_field_id AUTO_INCREMENT PRIMARY KEY, Player VARCHAR, Country VARCHAR, Year(s) won VARCHAR, Total INT, To par INT, Finish VARCHAR) CREATE TABLE minnesota_counties_ranked_by_per_capita_income (minnesota_counties_ranked_by_per_capita_income_id AUTO_INCREMENT PRIMARY KEY, County VARCHAR, Per capita income VARCHAR, Median household income VARCHAR, Median family income VARCHAR, Population INT, Number of households INT) CREATE TABLE won_lost_records (won_lost_records_id AUTO_INCREMENT PRIMARY KEY, Quarterback VARCHAR, Uniform No(s) INT, Games Started INT, Wins INT, Losses INT, Ties INT, Winning Pct. INT)  
SELECT Per capita income FROM minnesota_counties_ranked_by_per_capita_income WHERE Median family income = $50,755